U.S. patent number 7,873,292 [Application Number 11/954,645] was granted by the patent office on 2011-01-18 for image forming apparatus and transfer method thereof.
This patent grant is currently assigned to Samsung Electronics Co., Ltd.. Invention is credited to Jeong-hwan Kim, Se-ra Lee.
United States Patent |
7,873,292 |
Kim , et al. |
January 18, 2011 |
Image forming apparatus and transfer method thereof
Abstract
An image forming apparatus includes a moving unit which includes
a conveyer belt to move a recording medium, an attraction unit
which is disposed at a front head in a moving direction of the
recording medium and attracts the recording medium to the conveyer
belt, a plurality of transferring units including a photosensitive
material and a transfer roller to perform a transferring process of
the recording medium according to a plurality of colors, a power
supply to supply power to form an electric field in the
transferring unit and the attraction unit to perform transfer and
attraction of the recording medium, and a controller to control the
power supply to supply the power to the plurality of transferring
units corresponding to resistance values of second transferring
units among the plurality of transferring units, the second
transferring units disposed apart from a first transferring unit
that is located closest to the attraction unit with respect to the
moving direction of the recording medium.
Inventors: |
Kim; Jeong-hwan (Gunsan-si,
KR), Lee; Se-ra (Suwon-si, KR) |
Assignee: |
Samsung Electronics Co., Ltd.
(Suwon-si, KR)
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Family
ID: |
39262545 |
Appl.
No.: |
11/954,645 |
Filed: |
December 12, 2007 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20080159764 A1 |
Jul 3, 2008 |
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Foreign Application Priority Data
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Jan 2, 2007 [KR] |
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10-2007-0000275 |
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Current U.S.
Class: |
399/66 |
Current CPC
Class: |
G03G
15/1675 (20130101); G03G 15/0131 (20130101); G03G
2215/00632 (20130101); G03G 2215/00409 (20130101); G03G
2215/0138 (20130101); G03G 2215/00763 (20130101) |
Current International
Class: |
G03G
15/16 (20060101) |
Field of
Search: |
;399/66 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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10-228186 |
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Aug 1998 |
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JP |
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2003-316109 |
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Nov 2003 |
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JP |
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1999-38550 |
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Jun 1999 |
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KR |
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2005-66983 |
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Jun 2005 |
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KR |
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Other References
European Search Report dated May 8, 2008. cited by other .
European Search Report dated Aug. 8, 2008 issued in EP 07123838.0.
cited by other .
Thomson Scientific, London, GB; AN--"Database WPI Week
199844"--XP002489598--1998-516385. cited by other.
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Primary Examiner: Gray; David M
Assistant Examiner: Hyder; G. M.
Attorney, Agent or Firm: Stanzione & Kim, LLP
Claims
What is claimed is:
1. An image forming apparatus, comprising: an attraction unit to
attract a recording medium to a conveyer belt in the image forming
apparatus; a plurality of transferring units to perform a
transferring process of the recording medium; and a controller to
supply power to perform the transferring process by detecting a
leakage voltage and/or leakage current produced by the plurality of
transferring units and measuring a resistance value of the
attraction unit and any one of the plurality of transferring units
with a smallest leakage voltage and/or leakage current value.
2. The image forming apparatus of claim 1, wherein the transferring
process of the recording medium is performed by each of the
plurality of transferring units corresponding to a plurality of ink
colors.
3. The image forming apparatus of claim 1, wherein the controller
obtains a resistance value of the transferring unit furthest from
the attraction unit.
4. The image forming apparatus of claim 1, wherein the controller
simultaneously obtains the resistance value of the one of the
plurality of transferring units with the smallest leakage voltage
and/or leakage current value and the resistance value of the
attraction unit.
5. The image forming apparatus of claim 1, wherein the controller
determines a magnitude of power generated by the transferring
process corresponding to the recording medium according to the
obtained resistance values of the attraction unit and the one of
the plurality of transferring units with the smallest leakage
voltage and/or leakage current value.
6. The image forming apparatus of claim 4, wherein the controller
supplies the power at the determined magnitude to the plurality of
transferring units.
7. A transferring method of an image forming apparatus, comprising:
attracting a recording medium to a conveyer belt in the image
forming apparatus by an attraction unit; detecting a leakage
voltage and/or leakage current produced by a plurality of
transferring units that transfer the recording medium; obtaining a
resistance value of the attraction unit; measuring a resistance
value of any one of the plurality of transferring units with a
smallest leakage voltage and/or leakage current value; and
supplying power to the plurality of transferring units to perform a
transferring process of the recording medium based on the measured
resistance value of the attraction unit and the one of the
plurality of transferring units with the smallest leakage voltage
and/or leakage current value.
8. The method of claim 7, further comprising: obtaining a
resistance value of the transferring unit furthest from the
attraction unit.
9. The method of claim 7, further comprising: determining a
magnitude of the power generated by the transferring process
corresponding to the recording medium according to the obtained
resistance values; and supplying the power at the determined
magnitude to the plurality of transferring units.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. .sctn.119(a) from
Korean Patent Application No. 10-2007-0000275, filed on Jan. 2,
2007 in the Korean Intellectual Property Office, the disclosure of
which is incorporated herein in its entirety by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present general inventive concept relates to an image forming
apparatus. More particularly, the present general inventive concept
relates to an image forming apparatus that determines a transfer
voltage or a transfer current.
2. Description of the Related Art
A conventional image forming apparatus forms an image for
outputting contents generated by a computer program on a recording
medium. Particularly, the conventional image forming apparatus
forms an electrostatic latent image by scanning light to a
photosensitive medium, develops the electrostatic latent image with
a developer, and transfers and fixes the developed electrostatic
latent image on a paper so as to form an image.
FIG. 1 illustrates a transfer process of a conventional image
forming apparatus. As illustrated in FIG. 1, the conventional image
forming apparatus sets a transferring unit 2a disposed closest to
an attraction unit 1, which uses an attraction roller 1a, as a
reference transferring unit among a plurality of transferring units
2, and obtains a resistance value of the transferring unit 2a by
detecting a current flowing to the transferring unit 2a so as to
determine an optimal transfer voltage and/or current in a
pre-printing process which is performed before printing on a
recording medium. Herein, a resistance value of the transferring
unit 2a is obtained by using a photosensitive material, a conveyer
belt that passes the corresponding transferring unit 2a, and a
transfer roller that is disposed facing the photosensitive material
with respect to the conveyer belt and transfers a toner that has
been developed to a charged photosensitive material to the
recording medium.
Therefore, when the resistance value of the transferring unit 2a is
obtained, the conventional image forming apparatus detects a
current flowing to the attraction unit 1 and obtains a resistance
value thereof. In this case, the resistance value of the attraction
unit 1 is determined by the attraction roller (ATTR) 1a that
attracts the recording medium to the conveyor belt and a driving
roller that moves the recording medium to be transferred to the
transferring unit 2 by the conveyer belt.
When the recording medium enters into the attraction unit 1, the
conventional image forming apparatus obtains the resistance value
of the attraction unit 1 by detecting the current flowing thereto
so as to obtain a resistance value corresponding to the recording
medium.
An optimal transfer voltage for a transferring operation can be
determined by the resistance value obtained in such a manner.
However, the conventional image forming apparatus obtains the
resistance value of the transferring unit 2a located closest to the
attraction unit 1. Therefore, when power is applied to the
attraction unit 1 for obtaining the resistance value of the
attraction unit 1, a leakage current from the attraction unit 1
interacts between the transferring unit 2a and the attraction unit
1, and it is difficult to obtain the accurate resistance value of
the transferring unit 2a.
FIG. 2 illustrates a transferring process of the conventional image
forming apparatus for a recording medium with respect to time.
As illustrated in FIG. 2, the conventional image forming apparatus
obtains the resistance value of the transferring unit 2a during
time t1 to time t2, and then obtains the resistance value of the
attraction unit 1 during time t2 to time t3 after perception of the
resistance value of the transferring unit 2a is completed.
Then, at a time after passing time t4 to time t5 but before the
recording medium enters into the attraction unit 1, the
conventional image forming apparatus obtains a resistance value of
the recording medium entering the attraction unit 1 during time t5
to time t6. Through the obtained resistance value, the transfer
process is performed on the recording medium after time t6.
In this case, since the leakage current from the attraction unit 1
interacts between the attraction unit 1 and the transferring unit
2a, the resistance value of the transferring unit 2a and the
resistance value of the attraction unit 1 cannot be simultaneously
obtained, but has to be separately obtained during time t1 to time
t2 and time t2 to time t4, thereby increasing a pre-printing time
for printing the recording medium.
The above information disclosed in this Background section is only
for enhancement of understanding of the background of the present
general inventive concept, and therefore it may contain information
that does not form the prior art that is already known in this
country to a person of ordinary skill in the art.
SUMMARY OF THE INVENTION
The present general inventive concept provides an image forming
apparatus and a transferring method thereof to determine an
accurate transfer voltage and/or current while minimizing time
corresponding to a pre-printing process by obtaining a resistance
value of a transferring unit without an effect of a leakage current
of an attraction unit in the pre-printing process.
Additional aspects and utilities of the present general inventive
concept will be set forth in part in the description which follows
and, in part, will be obvious from the description, or may be
learned by practice of the general inventive concept.
The foregoing and/or other aspects and utilities of the present
general inventive concept are achieved by providing an image
forming apparatus comprising a moving unit comprising a conveyer
belt to move a recording medium, an attraction unit which is
disposed at a front head in a moving direction of the recording
medium to attract the recording medium to the conveyer belt, a
plurality of transferring units comprising a photosensitive
material and a transfer roller and to perform a transferring
process of the recording medium according to a plurality of colors,
a power supply to supply power to form an electric field in the
transferring unit and the attraction unit to perform transfer and
attraction operations of the recording medium, and a controller to
control the power supply to supply the power to the plurality of
transferring units corresponding to resistance values of second
transferring units among the plurality of transferring units, the
second transferring units disposed apart from a first transferring
unit that is located closest to the attraction unit with respect to
the moving direction of the recording medium.
The controller may comprise a voltage and/or current detector to
detect an amount of a voltage and/or current flowing in the second
transferring units and the attraction unit according to the power
supplied from the power supply, and a transfer voltage and/or
current determiner to obtain the resistance values of the second
transferring units by the detected current to determine a transfer
voltage.
The voltage and/or current detector may detect respective voltage
and/or current values when the recording medium is attracted to the
conveyer belt and when the recording medium is not attracted to the
conveyer belt, and the controller may obtain a resistance value
that corresponds to the recording medium through the detected
respective voltage and/or current values.
The controller may control respective times of obtaining the
resistance values of the second transferring units and of obtaining
the resistance value of the attraction unit to be overlapped with
each other when the recording medium is not attracted to the
conveyer belt.
The controller may obtain the resistance values of the second
transferring units and the resistance value of the attraction unit
when the recording medium is not attracted to the conveyer belt
within a certain period of time.
The controller may control to supply the power corresponding to the
resistance value of one of the second transferring units that is
located furthest in the moving direction of the recording medium
with reference to the plurality of transferring units.
The foregoing and/or other aspects and utilities of the present
general inventive concept may also be achieved by providing a
transferring method of an image forming apparatus comprising a
moving unit which comprises a conveyer belt to move a recording
medium, an attraction unit which is located at a head portion in a
moving direction of the recording medium and attracts the recording
medium to the conveyer belt, and a plurality of transferring units
which comprise a photosensitive material and a transfer roller and
perform a transferring process of the recording medium according to
a plurality of colors, the transferring method comprising:
detecting a voltage and/or current flowing in second transferring
units among the plurality of transferring units and the attraction
unit, the second transferring units located apart from a first
transferring unit that is located closest to the attraction unit
with respect to the moving direction of the recording medium,
obtaining resistance values of the second transferring units and a
resistance value of the attraction unit according to the detected
voltage and/or current, determining power of the transferring
process of the recording medium according to the obtained
resistance values of the second transferring units, and supplying
the determined power to the plurality of transferring units.
The detecting of the voltage and/or current may comprise detecting
respective voltage and/or current values when the recording medium
is attracted to the conveyer belt by the attraction unit and when
the recording medium is not attracted to the conveyer belt, and the
obtaining of the resistance values of the second transferring units
and the attraction unit comprises obtaining a resistance value that
corresponds to the recording medium through the detected respective
voltage or current values.
The obtaining of the resistance values of the second transferring
units and the attraction unit may comprise overlapping a time of
obtaining the resistance values of the second transferring units
and a time of obtaining the resistance value of the attraction unit
when the recording medium is not attracted to the conveyer belt
within a certain period of time.
The obtaining of the resistance values of the second transferring
units and the attraction unit may comprise obtaining the resistance
values of the second transferring units and the resistance value of
the attraction unit when the recording medium is not attracted to
the conveyer belt.
The detecting of the voltage and/or current may comprise detecting
the voltage and/or current of one of the second transferring units
located furthest in the moving direction of the recording medium
with reference to the plurality of transferring units.
The foregoing and/or other aspects and utilities of the present
general inventive concept may also be achieved by providing an
image forming apparatus, comprising an attraction unit to attract a
recording medium to a conveyer belt in the image forming apparatus,
a plurality of transferring units to perform a transferring process
of the recording medium, and a controller to supply power to
perform the transferring process by detecting a leakage voltage
and/or leakage current produced by the plurality of transferring
units and obtaining a resistance value of the attraction unit and
any one of the plurality of transferring units with a smallest
leakage voltage and/or leakage current value.
The transferring process of the recording medium may be performed
by each of the plurality of transferring units corresponding to a
plurality of ink colors.
The controller may obtain a resistance value of the transferring
unit furthest from the attraction unit.
The controller may simultaneously obtain the resistance value of
the one of the plurality of transferring units with the smallest
leakage voltage and/or leakage current value and the resistance
value of the attraction unit.
The controller may determine a magnitude of power generated by the
transferring process corresponding to the recording medium
according to the obtained resistance values of the attraction unit
and the one of the plurality of transferring units with the
smallest leakage voltage and/or leakage current value.
The controller may supply the power at the determined magnitude to
the plurality of transferring units.
The foregoing and/or other aspects and utilities of the present
general inventive concept may also be achieved by providing a
transferring method of an image forming apparatus, comprising
attracting a recording medium to a conveyer belt in the image
forming apparatus by an attraction unit, detecting a leakage
voltage and/or leakage current produced by a plurality of
transferring units that transfer the recording medium, obtaining a
resistance value of the attraction unit, obtaining a resistance
value of any one of the plurality of transferring units with a
smallest leakage voltage and/or leakage current value, and
supplying power to the plurality of transferring units to perform a
transferring process of the recording medium based on the obtained
resistance value of the attraction unit and the one of the
plurality of transferring units with the smallest leakage voltage
and/or leakage current value.
The method may further comprise obtaining a resistance value of the
transferring unit furthest from the attraction unit.
The method may further comprise determining a magnitude of the
power generated by the transferring process corresponding to the
recording medium according to the obtained resistance values, and
supplying the power at the determined magnitude to the plurality of
transferring units.
BRIEF DESCRIPTION OF THE DRAWINGS
These and/or other aspects and utilities of the present general
inventive concept will become apparent and more readily appreciated
from the following description of the embodiments, taken in
conjunction with the accompanying drawings of which:
FIG. 1 is a cross-section view of a transferring process of a
conventional image forming apparatus;
FIG. 2 illustrates a system obtaining process of the conventional
image forming apparatus;
FIG. 3 is a block diagram of an image forming apparatus according
to an exemplary embodiment of the present general inventive
concept;
FIG. 4 illustrates a transferring process of the image forming
apparatus according to an exemplary embodiment of the present
general inventive concept;
FIG. 5A to FIG. 5C illustrate interaction in the image forming
apparatus according to an exemplary embodiment of the present
general inventive concept;
FIG. 6 illustrates a system obtaining process of the image forming
apparatus according to an exemplary embodiment of the present
general inventive concept; and
FIG. 7 is a flowchart of a transferring method of the image forming
apparatus according to an exemplary embodiment of the present
general inventive concept.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to the embodiments of the
present general inventive concept, examples of which are
illustrated in the accompanying drawings, wherein like reference
numerals refer to like elements throughout. The embodiments are
described below so as to explain the present general inventive
concept by referring to the figures.
Hereinafter, an image forming apparatus 1 according to an exemplary
embodiment of the present general inventive concept will now be
described in further detail with reference to the accompanying
drawings.
FIG. 3 is a block diagram of an image forming apparatus 100
according to an exemplary embodiment of the present general
inventive concept, and FIG. 4 illustrates a transfer process of the
image forming apparatus 100 according to the exemplary embodiment
of the present general inventive concept.
As illustrated in FIG. 3, the image forming apparatus 100 includes
an attraction unit 10, a transferring unit 20, a power supply 30, a
moving unit 40, and a controller 50, and may be provided as a
printing apparatus having transferring units respectively
corresponding to colors including CMYK (i.e., cyan, magenta,
yellow, and black, respectively).
The attraction unit 10 includes an attraction roller 12 and a
driving roller 14, and attracts a recording medium P to a conveyer
belt 42 through which the recording medium is moved to the
transferring unit 20. As illustrated in FIG. 4, the recording
medium P is not attracted to the attraction unit 10 and the
recording medium P' is attracted to the attraction unit 10.
The transferring unit 20 includes a plurality of photoconductors
22a, 22b, 22c, and 22d, and a plurality of transfer rollers 24a,
24b, 24c, and 24d that transfer ink onto a recording medium
according to a plurality of colors. The transferring unit 20 is
connected with the attraction unit 10 by the conveyer belt 42. The
plurality of transfer rollers 24a, 24b, 24c, and 24d are disposed
opposite to the plurality of photoconductors 22a, 22b, 22c, and
22d, respectively. The conveyer belt 42 separates the plurality of
transfer rollers 24a, 24b, 24c, and 24d from the plurality of
photoconductors 22a, 22b, 22c, and 22d, respectively, and transfers
a toner developed on each of the plurality of photoconductors 22a,
22b, 22c, and 22d to the recording medium. Herein, the transferring
unit 20 includes a first transferring unit 20a and second
transferring units 20b, 20c, and 20d. The first transferring unit
20a is disposed closest to the attraction unit 10 with regard to
the second transferring units 20b, 20c, and 20d, which are disposed
apart from the first transferring unit 20a with respect to a moving
direction of the recording medium. A number of transferring units
20 may be provided so as to respectively correspond to the CMYK
according to an exemplary embodiment of the present general
inventive concept.
The power supply 30 supplies an attraction power and a transfer
power to the attraction unit 10 and the transferring unit 20,
respectively, so as to form an electric field to help perform the
attraction and transfer of the recording medium.
The moving unit 40 includes the conveyer belt 42, and moves the
recording medium to the transferring unit 20 from the attraction
unit 10.
The controller 50 controls the power supply 30 to supply power that
corresponds to resistance values of the second transferring units
20b, 20c, and 20d, to the first transferring unit 20a and the
second transferring units 20b, 20c, and 20d.
Additionally, the controller 50 obtains one resistance value among
the second transferring units 20b, 20c, and 20d, and the transfer
power may be supplied corresponding to the obtained resistance
value. More specifically, the controller 50 may obtain a resistance
value of the transferring unit 20d, which is disposed furthest from
the attraction unit 10 and therefore contacts the recording medium
last during a printing operation.
The controller 50 according to an exemplary embodiment of the
present general inventive concept may include a voltage and/or
current detector 50a and a transfer voltage and/or current
determiner 50b. The voltage and/or current detector 50a detects the
size of a voltage and/or current flowing to the transferring unit
20, and the transfer voltage and/or current determiner 50b obtains
the resistance value of the second transferring units 20b, 20c, and
20d according to the detected voltage and/or current and determines
a transfer voltage or a transfer current.
The voltage and/or current detector 50a is formed of a circuit to
feed back the voltage and/or current flowing in the transferring
unit 20 to the power supply 30, and the transfer voltage and/or
current determiner 50b is provided as software that determines an
amount of the transfer voltage and/or current based on the
resistance value obtained through the detected voltage and/or
current.
FIG. 5A illustrates an amount of current flowing in each of the
transferring units 20a, 20b, 20c, and 20d, when power is applied or
not applied to the attraction unit 10. As illustrated in FIG. 5A,
when the power is applied to the attraction unit 10, the first
transferring unit 20a disposed closest to the attraction unit 10
has a leakage current value of 4.4 .mu.A (=8.6 .mu.A-4.2 .mu.A),
which is a largest value, and the second transferring unit 20d,
which is disposed farthest from the attraction unit 10, has a
leakage current value of 0.2 .mu.A (=9.1 .mu.A-8.9 .mu.A) which is
a smallest value.
FIG. 5B illustrates an amount of current flowing in each of the
transferring units 20a, 20b, 20c, and 20d according to an amount of
voltage applied to the transferring units 20a, 20b, 20c, and 20d
when power is applied to the attraction unit 10 and the
transferring units 20a, 20b, 20c, and 20d.
As illustrated in FIG. 5B, the amount of the current increases as
the amount of the voltage applied to the transferring unit 20
increases, and the first transferring unit 20a, which is disposed
closest to the attraction unit 10 at a first pod position (i.e.,
1.sup.st Pod), has leakage current values (i.e., delta current
values) of 3.9.mu.A and 4.4.mu.A -corresponding to applied powers
of 90V and 900V, respectively, and the second transferring unit
20d, which is disposed farthest from the attraction unit 10 at a
fourth pod position (i.e., 4.sup.th Pod), has leakage current
values of 0.4.mu.A and -0.2.mu.A corresponding to applied powers of
90V and 900V, respectively. The TR Pod Position illustrated in FIG.
5B refers to a location of the transferring units 20 with respect
to the attraction unit 10. That is, the first transferring unit 20a
is disposed at the first pod position which is closest to the
attraction unit 10. The second, third, and fourth transferring
units 20b, 20c, and 20d are respectively disposed at the second,
third, and fourth pod positions which are located further away from
the attraction unit 10 than the first transferring unit 20a.
That is, the transferring unit 20a, which is disposed closest to
the attraction unit 10, has the largest leakage current value, and
the transferring unit 20d, which is disposed farthest from the
attraction unit 10, has the smallest leakage current value.
FIG. 5C illustrates an amount of current flowing in each of the
transferring units 20a, 20b, 20c, and 20d according to a type of
recording medium when power is applied to the attraction unit 10
and the transferring units 20. As illustrated in FIG. 5C, the
second transferring unit 20d, which is disposed farthest from the
attraction unit 10, has the smallest leakage current value
corresponding to the power applied to the attraction unit 10,
regardless of the type of the recording medium used.
As described above, when the resistance value is obtained by
setting the second transferring unit 20d, which is disposed
farthest from the attraction unit 10, as a reference transferring
unit in the pre-printing process of obtaining the resistance values
of the first transferring unit 20a and the second transferring
units 20b, 20c, and 20d, the leakage current value becomes less
than 1.0 .mu.A, which is a smaller value than values corresponding
to any of the other second transferring units 20b and 20c due to a
minimized interaction between the second transferring unit 20d and
the attraction unit 10.
FIG. 6 illustrates a transferring process of the image forming
apparatus 100 corresponding to the recording medium with respect to
time according to an exemplary embodiment of the present general
inventive concept.
As illustrated in FIG. 6, since the image forming apparatus 100 can
minimize an interaction between the attraction unit 10 and the
transferring unit 20, the image forming apparatus 100 can obtain a
resistance value of the attraction unit 10 while obtaining a
resistance value of the first transferring unit 20a during time t1
to time t2. That is, the controller 50 can control time of
obtaining the resistance values of the respective second
transferring units 20b, 20c, and 20d to overlap the time of
obtaining the attraction unit 10, and can simultaneously obtain the
resistance values of the second transferring units 20b, 20c, and
20d and the resistance value of the attraction unit 10.
At a time after passing time t3 to time t4 but before the recording
medium enters the attraction unit 10, the controller 50 obtains the
resistance value of the recording medium that enters the attraction
unit 10 during time t4 to time t5. With the above-obtained
resistance values, a transferring process is performed on the
recording medium after time t5.
Therefore, since the image forming apparatus 100 according to an
exemplary embodiment of the present general inventive concept can
obtain the resistance value of the transferring unit 20 and the
resistance value of the attraction unit 10 according to the
transfer power and the attraction power applied from the power
supply 30 during time t1 to time t2, a time corresponding to a
pre-printing process can be reduced.
If the leakage voltage or leakage current from the transferring
unit 20 attraction is less than a predetermined value that does not
affect the interaction between the attraction unit 10 and the
transferring unit 20, any other second transferring unit 20b or 20c
may be set as the reference transferring unit to obtain the
resistance value. That is, the controller 50 can obtain the
resistance value by setting any one of the transferring units 20b,
20c, and 20d which are disposed apart from the first transferring
unit 20a with respect to the moving direction of the recording
medium, as the reference transferring unit.
A transferring method of the image forming apparatus 100 according
to an exemplary embodiment of the present general inventive concept
will be described in further detail with reference to FIG. 7.
Referring to FIGS. 3-4 and 7, in operation S10, the controller 50
detects a voltage or a current flowing to the attraction unit 10
and the second transferring units 20b, 20c, and 20d. The controller
50 may detect the voltage or the current flowing in at least one of
the second transferring units 20b, 20c, and 20d. Furthermore, the
transferring unit 20d may be ideally utilized since it is disposed
furthest from the attraction unit 10 and therefore contacts the
recording medium last during a printing operation.
In operation S20, the controller 50 obtains the resistance values
of the attraction unit 10 and the second transferring units 20b,
20c, and 20d according to the voltage or current obtained in
operation S10. In operation S30, the controller 50 determines the
power of the transferring process corresponding to the recording
medium according to the resistance values obtained in operation
S20.
In operation S40, the controller 50 controls the power supply 30 to
supply the power determined in operation S30 to the plurality of
transferring units 20a, 20b, 20c, and 20d.
An embodiment of the present general inventive concept described in
detail above is not restricted to the above description, and
various modifications can be made within the scope of the appended
claims.
As described above, an image forming apparatus and a transferring
method of accurately determining a power of a transferring process
of a recording medium regardless of an interaction between an
attraction unit and a transferring unit can be provided.
In addition, an image forming apparatus and a transferring method
of reducing a time in a pre-printing process of obtaining
resistance values of an attraction unit and a transferring unit can
be provided.
Although a few embodiments of the present general inventive concept
have been shown and described, it will be appreciated by those
skilled in the art that changes may be made in these embodiments
without departing from the principles and spirit of the general
inventive concept, the scope of which is defined in the appended
claims and their equivalents.
* * * * *